Certain types of discharge lamps require a particular orientation for the lamp to achieve proper operation. Such lamps are shown, for example, in U.S. Pat. No. 3,858,078, wherein the lamp has an arched arc tube; and U.S. Pat. No. 4,990,819, wherein the arc tube is mounted skewed relative to the longitudinal axis. These lamps employ bases that may have an index pin projecting from the base to cooperate with a socket to maintain the lamp in the proper orientation.
In the past it has been the practice to weld or solder the pin in place prior to assembly to the lamp. Welding is an expensive operation and soldering requires the usually brass base to be nickel-plated to cover the discoloration resulting from the soldering operation. Additionally, the use of lead-bearing solders can be an environmental hazard and the use of silver solders is too expensive.